Biodiversity

Question 1

What is sampling?

Answer 1

Taking measurements of a limited number of individual organisms present in a particular area

Question 2

What does the abundance of an organism tell us

Answer 2

The number of individuals of a species present in an area

Question 3

What is random sampling

Answer 3

Means selecting individuals by chance

Question 4

What is non random sampling

Answer 4

When the sample is not random

Question 5

What are the three main techniques if non random sampling

Answer 5

Opportunistic
Stratified
Systematic

Question 6

Explain opportunistic sampling

Answer 6

Weakest form of sampling. Uses organisms the are conveniently available.

Question 7

Explain stratified sampling

Answer 7

Population can be divided into a number of strata based in particular characteristics. A random sample is then taken from each strata proportional to its size.

Question 8

Explain systematic sampling

Answer 8

Areas within an overall population are identified and sampled separately. Often carried out using a line or belt transect.

Question 9

What is sample bias

Answer 9

Selection may be biased. May be by accident or deliberate. Effects may be reduced using random sampling.

Question 10

What is chance

Answer 10

Organisms selected may by chance not be representative of the whole population. Can never be completely removed. Can be minimised using a larger sample.

Question 11

importance of biodiversity

Answer 11

essential in maintaining a balanced ecosystem as all species are dependant on each other
we rely on ecosystems as they supply us with food, oxygen and other materials

Question 12

different levels biodiversity can be measured at

Answer 12

habitat biodiversity
species bidiversity
genetic biodiversity

Question 13

biodiversity

Answer 13

variety of living organisms present in an area

Question 14

habitat biodiversity

Answer 14

refers to the number of different habitats found within an area
greater the habitat biodiversity the higher the species biodiversity

Question 15

species richness

Answer 15

the number of different species living in a particular area

Question 16

species evenness

Answer 16

a comparison of the numbers of individuals of each species living in a community

Question 17

genetic biodiversity

Answer 17

refers to the variety of genes that make up a species

Question 18

point quadrat

Answer 18

consists of a frame containing a horizontal bar at set intervals a long pin can be pushed through to the ground and each species of plant the pin touches is recorded

Question 19

frame quadrat

Answer 19

consists of a square frame divided into a grid of equal sections the type and number of species within each section is recorded

Question 20

using frame quadrats

density

Answer 20

if individual plants can be seen clearly count them in a 1m by 1m quadrat and this will give you the density per square metre

Question 21

using frame quadrats

frequency

Answer 21

used when individuals are hard to count, using small grids within the quadrat count the amount of sqaures the species is present in and find thee percentage